Unlock instant, AI-driven research and patent intelligence for your innovation.

Casting method of silicon ingot

A silicon ingot and polysilicon technology, applied in the field of silicon ingot casting, can solve the problems of crystal growth failure and floating, and achieve the effect of size increase

Inactive Publication Date: 2018-06-12
QINGDAO XIAOMIXING ELECTRONICS TECH CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Since the density of solid silicon is lower than that of liquid silicon, the solid silicon placed at the bottom of the crucible may float up after being wetted by contact with liquid silicon, resulting in the failure of induced crystal growth.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] A method for casting a silicon ingot, comprising the following steps:

[0022] Step 1, charging in the crucible: first, lay the bottom layer raw material on the bottom surface of the crucible, the bottom layer raw material includes polysilicon powder; secondly, lay the middle layer raw material on the bottom layer raw material, the middle layer raw material is made of multiple pieces Splicing monocrystalline silicon wafers; again, filling the upper layer raw material on the middle layer raw material, the upper layer raw material is composed of polycrystalline silicon material; the polycrystalline silicon material is purified and added with doping according to the target resistivity of the silicon ingot to be formed. miscellaneous agent.

[0023] Step 2, placing the charged crucible in an ingot casting furnace, and evacuating the ingot casting furnace; heating the bottom of the crucible to a certain temperature, which makes all the parts at the bottom of the crucible Th...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a casting method of a silicon ingot. The casting method comprises the following steps: loading in a crucible, wherein a bottom-layer raw material comprises a polycrystalline silicon powder, a middle-layer raw material is formed by splicing monocrystalline silicon chips, and an upper-layer raw material is a polycrystalline silicon material; placing the crucible in an ingot casting furnace, vacuum-pumping and sintering the polycrystalline silicon powder to fix the monocrystalline silicon chips; controlling the vertical temperature gradient in the furnace, so that the upper parts of the monocrystalline silicon chips are melted, and the polycrystalline silicon material is melted; controlling the vertical temperature gradient in the furnace, so that grains grow up alongthe un-melted monocrystalline silicon chips, and the silicon ingot is obtained. The casting method disclosed by the invention has the benefits that the grain size of the silicon ingot can be improved,the photoelectric conversion efficiency of a silicon cell made of the silicon ingot is improved, and the production cost can be reduced.

Description

technical field [0001] The invention relates to the field of photovoltaic product manufacturing, in particular to a method for casting silicon ingots. Background technique [0002] The main raw material of solar cells is silicon crystal, including monocrystalline silicon and polycrystalline silicon. Monocrystalline silicon is mainly prepared by the Czochralski method, which is characterized by complete crystal structure, low number of crystal defects, and high photoelectric conversion efficiency of the prepared silicon cells. However, the cost of silicon cells prepared by this method is relatively high, and the production efficiency is low. Due to the characteristics of its production technology, the monocrystalline silicon ingot produced by the Czochralski method is cylindrical, and the utilization rate of the material is low in the process of cutting into square cells. [0003] Polysilicon is generally prepared by directional solidification, using a square crucible, whic...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C30B11/00C30B29/06
CPCC30B11/003C30B11/002C30B29/06
Inventor 曲立辉
Owner QINGDAO XIAOMIXING ELECTRONICS TECH CO LTD